An aseismic slip transient on the North Anatolian Fault
An aseismic slip transient on the North Anatolian Fault
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DOI：
10.1002/2016gl068250
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发表时间：
2016-04-16
影响因子：
5.2
通讯作者：
Renard, Francois
中科院分区：
文献类型：
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作者：
Rousset, Baptiste;Jolivet, Romain;Renard, Francois
合成孔径雷达（SAR）卫星群具有短重复时间采集，可以以前所未有的时间分辨率探索活动断层的行为。土耳其的北安那托利亚断层（NAF），至少自1944年在Ismetpasa附近发生的M-w 7.3级地震以来，一条80公里长的断层一直在蠕动，目前的干涉合成孔径雷达（InSAR）得出的平均蠕动速率为每年8 +/- 3毫米（即NAF长期滑动速率的三分之一）。我们使用cosmos - skymed星座获得的密集SAR图像集来量化1年来蠕变的空间分布和时间演变。我们确定了一个主要的地震滑动爆发，跨越31天，最大滑动为2厘米，在地表和4公里深度之间。这一结果表明，沿NAF这一段的断层蠕变并不像以前认为的那样以稳定的速度发生，这突出表明需要修改我们对潜在断层力学的理解。
Constellations of Synthetic Aperture Radar (SAR) satellites with short repeat time acquisitions allow exploration of active faults behavior with unprecedented temporal resolution. Along the North Anatolian Fault (NAF) in Turkey, an 80 km long section has been creeping at least since the 1944, M-w 7.3 earthquake near Ismetpasa, with a current Interferometric Synthetic Aperture Radar (InSAR)-derived average creep rate of 8 +/- 3 mm/yr (i.e., a third of the NAF long-term slip rate). We use a dense set of SAR images acquired by the COSMO-SkyMed constellation to quantify the spatial distribution and temporal evolution of creep over 1 year. We identify a major burst of aseismic slip spanning 31 days with a maximum slip of 2 cm, between the surface and 4 km depth. This result shows that fault creep along this section of the NAF does not occur at a steady rate as previously thought, highlighting a need to revise our understanding of the underlying fault mechanics.